1. Field of the Invention
The present invention relates to a vibration motor, and more particularly, to a vibration motor provided with a blocking body of a commutator's breakaway enabling to maintain the commutator in fixed status without breakaway from a rotating shaft when an external force is applied thereon.
2. Description of the Related Art
In general, vibration motor are used to notify the users of the reception of a communication through their vibration, the motor being installed in a mobile communication device, such as mobile phones, and one of examples thereof is illustrated in FIG. 5.
As shown, a conventional motor 300 is composed of a housing 310, an output bearing 320, an opposite output bearing 330, a rotating shaft 340, a magnet 350, a coil 360, an eccentric pendulum 370, a blocking body 380, and a commutator 390.
The housing 310 is comprised of an outer housing 311 serving to an outer case of the motor 300 and an inner housing 315 being inwardly integrally extended from the outer housing 311.
The output bearing 320 is forcedly combined with the inlet portion of the housing 310, and the opposite output bearing 330 is forcedly combined with the end of the inner housing 315 opposite to the output bearing 320.
The rotating shaft 340 is installed in the inner housing 315 in order to pass through the output bearing 320 and the opposite output bearing 330 and be rotatably supported by them, and the eccentric pendulum 370 is eccentrically combined with a portion of the shaft 340 being outwardly exposed from the housing 310.
The magnet 350 is attached to an outer periphery surface of the inner housing 315, and the coil 360 is attached to an inner periphery surface of the outer housing 311 to be opposed to the magnet 350.
The blocking body 380 is forcedly combined with the shaft 340 and the commutator 390 is disposed on an outer periphery surface of the body 380.
However, in the conventional vibration motor 300, in order to obtain enough maintaining force with the rotating motor 340, the blocking body 380 should be formed to have an axially increased thickness considering non-uniform inner diameter of the body 380. Therefore, the length of the magnet 350 should be decreased as much as the increased thickness of the body 380 in the limited space, whereby bring to deterioration of a magnetic circuit and block for enhancing characteristic of the motor 300.